Logical Fallacies: Definition Version

Slippery Slope

This is a conclusion based on the premise that if A happens, then eventually through a series of small steps, through B, C,..., X, Y, Z will happen, too, basically equating A and Z. So, if we don't want Z to occur, A must not be allowed to occur either.

Hasty Generalization

This is a conclusion based on insufficient or biased evidence. In other words, you are rushing to a conclusion before you have all the relevant facts.

Post hoc ergo propter hoc

This is a conclusion that assumes that if 'A' occurred after 'B' then 'B' must have caused 'A.'

Genetic Fallacy

This conclusion is based on an argument that the origins of a person, idea, institute, or theory determine its character, nature, or worth

Begging the Claim

The conclusion that the writer should prove is validated within the claim.

Circular Argument

This restates the argument rather than actually proving it

Either/or

This is a conclusion that oversimplifies the argument by reducing it to only two sides or choices.

Ad hominem

This is an attack on the character of a person rather than his or her opinions or arguments

Ad populum/Bandwagon Appeal

This is an appeal that presents what most people, or a group of people think, in order to persuade one to think the same way. Getting on the bandwagon is one such instance of an ad populum appeal.

Red Herring

This is a diversionary tactic that avoids the key issues, often by avoiding opposing arguments rather than addressing them.

Straw Man

This move oversimplifies an opponent's viewpoint and then attacks that hollow argument.

Moral Equivalence

This fallacy compares minor misdeeds with major atrocities, suggesting that both are equally immoral.